Detailed Product Description

Indirect Pumped System

This system design is common in northern climates, where freezing weather occurs more frequently. An antifreeze solution circulates through the collector, and a heat exchanger transfers the heat from the antifreeze solution to the tank water. When toxic heat exchange fluids are used, a double-walled exchanger is required. Generally, if the heat exchanger is installed in the storage tank, it should be in the lower half of the tank.

The system  is an example of this system type. Here a heat transfer solution is pumped through the collector in a closed loop. The loop includes the collector, connecting piping, the pump, an expansion tank and a heat exchanger. A heat exchanger coil in the lower half of the storage tank transfers heat from the heat transfer solution to the potable water in the solar storage tank. An alternative of this design is to wrap the heat exchanger around the tank. This keeps it from contact with potable water.

The brain of the system is a differential controller. In conjunction with collector and tank temperature sensors, the controller determines when the pump should be activated to direct the heat transfer fluid through the collector.

The fluid used in this system is a mixture of distilled water and antifreeze similar to that used in automobiles. This type of fluid freezes only at extremely low temperatures so the system is protected from damage caused by severe cold